1. Technical Field
The present invention relates to a light source device and an observation apparatus.
2. Related Art
A light source device that selectively extracts light having a predetermined wavelength to emit the extracted light has been known (for example, see JP-A-1-102415).
In JP A-1-102415, the light source device uses a Fabry-Perot variable interference unit (interference filter) in order to extract light having a predetermined wavelength among light rays from a light source. Specifically, in the device described in JP A-1-102415, the light from the light source is rendered into parallel light by a lens, and the parallel light is incident on the interference filter.
In the light source device described in JP A-1-102415, it is possible to reduce a size of the light source device by using the interference filter as compared to a case where other spectroscopic devices such as an acousto-optic tunable filter (AOTF) or a liquid crystal tunable filter (LCTF) is used.
In general, the above-mentioned interference filter causes light to be incident on a region where a pair of reflection films faces each other and emits light having a predetermined wavelength. In the light source device using such an interference filter, in order to suppress a loss in light amount of illumination light, it is conceivable that areas of the reflection films of the interference filter are increased such that the light from the light source is incident on the reflection films.
However, when the areas of the reflection films are increased, the reflection film may be easily bent, and resolution thereof may be degraded.